In the field of digital communications, digital signals are often represented on a complex plane to intuitively represent a relationship between signals, and such a graphic representation is a constellation diagram.
Most current communications systems use a square constellation diagram. This constellation diagram has advantages of being easily modulated and demodulated. However, for this constellation diagram, there is still improvement room for bit error rate and signal to noise ratio performance. Moreover, currently, time-frequency resources are increasingly cherished, electronic components have continuously lowered prices and continuously improved processing capabilities, and therefore it seems to be more cost-effective to exchange relatively complex modulation and demodulation processes for higher usage of time-frequency resources.
In the prior art, a hexagonal lattice constellation diagram is used. This lattice constellation diagram has a closer arrangement. Therefore, if quantities of points are the same and distances between points are also the same, this hexagonal lattice constellation diagram has less average energy than a quadrilateral constellation diagram does, thereby having better bit error rate and signal to noise ratio performance.
In a process of improving the foregoing constellation diagram, it is found that there is still improvement room for the prior art.
In the prior art, although bit error rate-signal to noise ratio performance is improved by means of an orthohexagonal constellation diagram, the constellation diagram can be further improved to further improve the bit error rate-signal to noise ratio performance.